From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 1A5096B02C3 for ; Thu, 25 May 2017 16:33:57 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id e7so235038908pfk.9 for ; Thu, 25 May 2017 13:33:57 -0700 (PDT) Received: from mga09.intel.com (mga09.intel.com. [134.134.136.24]) by mx.google.com with ESMTPS id z66si29142522pgz.422.2017.05.25.13.33.55 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 25 May 2017 13:33:55 -0700 (PDT) From: "Kirill A. Shutemov" Subject: [PATCHv1, RFC 4/8] x86/mm: Handle boot-time paging mode switching at early boot Date: Thu, 25 May 2017 23:33:30 +0300 Message-Id: <20170525203334.867-5-kirill.shutemov@linux.intel.com> In-Reply-To: <20170525203334.867-1-kirill.shutemov@linux.intel.com> References: <20170525203334.867-1-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Linus Torvalds , Andrew Morton , x86@kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: Andi Kleen , Dave Hansen , Andy Lutomirski , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" This patch adds detection of 5-level paging at boot-time and adjusts virtual memory layout and folds p4d page table layer if needed. Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm/page_64_types.h | 13 +++---- arch/x86/include/asm/pgtable_64_types.h | 37 +++++++++++++------- arch/x86/include/asm/processor.h | 2 +- arch/x86/kernel/head64.c | 62 +++++++++++++++++++++++++-------- arch/x86/kernel/head_64.S | 16 +++++---- arch/x86/mm/kaslr.c | 2 +- 6 files changed, 90 insertions(+), 42 deletions(-) diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index 0126d6bc2eb1..26056ef366b8 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -36,24 +36,21 @@ * hypervisor to fit. Choosing 16 slots here is arbitrary, but it's * what Xen requires. */ -#ifdef CONFIG_X86_5LEVEL -#define __PAGE_OFFSET_BASE _AC(0xff10000000000000, UL) -#else -#define __PAGE_OFFSET_BASE _AC(0xffff880000000000, UL) -#endif +#define __PAGE_OFFSET_BASE57 _AC(0xff10000000000000, UL) +#define __PAGE_OFFSET_BASE48 _AC(0xffff880000000000, UL) #if defined(CONFIG_RANDOMIZE_MEMORY) || defined(CONFIG_X86_5LEVEL) #define __PAGE_OFFSET page_offset_base #else -#define __PAGE_OFFSET __PAGE_OFFSET_BASE +#define __PAGE_OFFSET __PAGE_OFFSET_BASE48 #endif /* CONFIG_RANDOMIZE_MEMORY */ #define __START_KERNEL_map _AC(0xffffffff80000000, UL) /* See Documentation/x86/x86_64/mm.txt for a description of the memory map. */ #ifdef CONFIG_X86_5LEVEL -#define __PHYSICAL_MASK_SHIFT 52 -#define __VIRTUAL_MASK_SHIFT 56 +#define __PHYSICAL_MASK_SHIFT (p4d_folded ? 52 : 46) +#define __VIRTUAL_MASK_SHIFT (p4d_folded ? 47 : 56) #else #define __PHYSICAL_MASK_SHIFT 46 #define __VIRTUAL_MASK_SHIFT 47 diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index a09f2fa91e09..46f52da75e16 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -19,6 +19,12 @@ typedef unsigned long pgprotval_t; typedef struct { pteval_t pte; } pte_t; +#ifdef CONFIG_X86_5LEVEL +extern unsigned int p4d_folded; +#else +#define p4d_folded 1 +#endif + extern unsigned int pgdir_shift; extern unsigned int ptrs_per_p4d; @@ -79,23 +85,30 @@ extern unsigned int ptrs_per_p4d; /* See Documentation/x86/x86_64/mm.txt for a description of the memory map. */ #define MAXMEM _AC(__AC(1, UL) << MAX_PHYSMEM_BITS, UL) -#ifdef CONFIG_X86_5LEVEL -#define VMALLOC_SIZE_TB _AC(16384, UL) -#define __VMALLOC_BASE _AC(0xff92000000000000, UL) -#define __VMEMMAP_BASE _AC(0xffd4000000000000, UL) -#else -#define VMALLOC_SIZE_TB _AC(32, UL) -#define __VMALLOC_BASE _AC(0xffffc90000000000, UL) -#define __VMEMMAP_BASE _AC(0xffffea0000000000, UL) -#endif + +#ifndef __ASSEMBLY__ +#define __VMALLOC_BASE48 0xffffc90000000000 +#define __VMALLOC_BASE57 0xff92000000000000 + +#define VMALLOC_SIZE_TB48 32UL +#define VMALLOC_SIZE_TB57 16384UL + +#define __VMEMMAP_BASE48 0xffffea0000000000 +#define __VMEMMAP_BASE57 0xffd4000000000000 + #if defined(CONFIG_RANDOMIZE_MEMORY) || defined(CONFIG_X86_5LEVEL) #define VMALLOC_START vmalloc_base +#define VMALLOC_SIZE_TB (!p4d_folded ? VMALLOC_SIZE_TB57 : VMALLOC_SIZE_TB48) #define VMEMMAP_START vmemmap_base #else -#define VMALLOC_START __VMALLOC_BASE -#define VMEMMAP_START __VMEMMAP_BASE +#define VMALLOC_START __VMALLOC_BASE48 +#define VMALLOC_SIZE_TB VMALLOC_SIZE_TB48 +#define VMEMMAP_START __VMEMMAP_BASE48 #endif /* CONFIG_RANDOMIZE_MEMORY */ -#define VMALLOC_END (VMALLOC_START + _AC((VMALLOC_SIZE_TB << 40) - 1, UL)) + +#define VMALLOC_END (VMALLOC_START + (VMALLOC_SIZE_TB << 40) - 1) +#endif + #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) /* The module sections ends with the start of the fixmap */ #define MODULES_END __fix_to_virt(__end_of_fixed_addresses + 1) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 65663de9287b..92c3f33f7682 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -854,7 +854,7 @@ static inline void spin_lock_prefetch(const void *x) IA32_PAGE_OFFSET : TASK_SIZE_MAX) #define STACK_TOP TASK_SIZE_LOW -#define STACK_TOP_MAX TASK_SIZE_MAX +#define STACK_TOP_MAX (!p4d_folded ? TASK_SIZE_MAX : DEFAULT_MAP_WINDOW) #define INIT_THREAD { \ .sp0 = TOP_OF_INIT_STACK, \ diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index d4e8d4beeb62..47629f3e32aa 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -39,26 +39,54 @@ static unsigned int __initdata next_early_pgt; pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); #ifdef CONFIG_X86_5LEVEL -unsigned int pgdir_shift = 48; +unsigned int pgdir_shift = 39; EXPORT_SYMBOL(pgdir_shift); -unsigned int ptrs_per_p4d = 512; +unsigned int ptrs_per_p4d = 1; EXPORT_SYMBOL(ptrs_per_p4d); #endif -#if defined(CONFIG_RANDOMIZE_MEMORY) || defined(CONFIG_X86_5LEVEL) -unsigned long page_offset_base = __PAGE_OFFSET_BASE; +unsigned long page_offset_base = __PAGE_OFFSET_BASE48; EXPORT_SYMBOL(page_offset_base); -unsigned long vmalloc_base = __VMALLOC_BASE; +unsigned long vmalloc_base = __VMALLOC_BASE48; EXPORT_SYMBOL(vmalloc_base); -unsigned long vmemmap_base = __VMEMMAP_BASE; +unsigned long vmemmap_base = __VMEMMAP_BASE48; EXPORT_SYMBOL(vmemmap_base); -#endif static void __init *fixup_pointer(void *ptr, unsigned long physaddr) { return ptr - (void *)_text + (void *)physaddr; } +static unsigned long __init *fixup_long(void *ptr, unsigned long physaddr) +{ + return fixup_pointer(ptr, physaddr); +} + +#ifdef CONFIG_X86_5LEVEL +static unsigned int __init *fixup_int(void *ptr, unsigned long physaddr) +{ + return fixup_pointer(ptr, physaddr); +} + +static void __init check_la57_support(unsigned long physaddr) +{ + if (native_cpuid_eax(0) < 7) + return; + + if (!(native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) + return; + + *fixup_int(&p4d_folded, physaddr) = 0; + *fixup_int(&pgdir_shift, physaddr) = 48; + *fixup_int(&ptrs_per_p4d, physaddr) = 512; + *fixup_long(&page_offset_base, physaddr) = __PAGE_OFFSET_BASE57; + *fixup_long(&vmalloc_base, physaddr) = __VMALLOC_BASE57; + *fixup_long(&vmemmap_base, physaddr) = __VMEMMAP_BASE57; +} +#else +static void __init check_la57_support(unsigned long physaddr) {} +#endif + void __init __startup_64(unsigned long physaddr) { unsigned long load_delta, *p; @@ -68,6 +96,8 @@ void __init __startup_64(unsigned long physaddr) pmdval_t *pmd, pmd_entry; int i; + check_la57_support(physaddr); + /* Is the address too large? */ if (physaddr >> MAX_PHYSMEM_BITS) for (;;); @@ -85,9 +115,14 @@ void __init __startup_64(unsigned long physaddr) /* Fixup the physical addresses in the page table */ pgd = fixup_pointer(&early_top_pgt, physaddr); - pgd[pgd_index(__START_KERNEL_map)] += load_delta; - - if (IS_ENABLED(CONFIG_X86_5LEVEL)) { + p = pgd + pgd_index(__START_KERNEL_map); + if (p4d_folded) + *p = (unsigned long)level3_kernel_pgt; + else + *p = (unsigned long)level4_kernel_pgt; + *p += _PAGE_TABLE - __START_KERNEL_map + load_delta; + + if (!p4d_folded) { p4d = fixup_pointer(&level4_kernel_pgt, physaddr); p4d[511] += load_delta; } @@ -109,7 +144,7 @@ void __init __startup_64(unsigned long physaddr) pud = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr); pmd = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr); - if (IS_ENABLED(CONFIG_X86_5LEVEL)) { + if (!p4d_folded) { p4d = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr); i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD; @@ -151,8 +186,7 @@ void __init __startup_64(unsigned long physaddr) } /* Fixup phys_base */ - p = fixup_pointer(&phys_base, physaddr); - *p += load_delta; + *fixup_long(&phys_base, physaddr) += load_delta; } /* Wipe all early page tables except for the kernel symbol map */ @@ -185,7 +219,7 @@ int __init early_make_pgtable(unsigned long address) * critical -- __PAGE_OFFSET would point us back into the dynamic * range and we might end up looping forever... */ - if (!IS_ENABLED(CONFIG_X86_5LEVEL)) + if (p4d_folded) p4d_p = pgd_p; else if (pgd) p4d_p = (p4dval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base); diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 6225550883df..2009d9849e98 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -104,7 +104,10 @@ ENTRY(secondary_startup_64) /* Enable PAE mode, PGE and LA57 */ movl $(X86_CR4_PAE | X86_CR4_PGE), %ecx #ifdef CONFIG_X86_5LEVEL + testl $1, p4d_folded(%rip) + jnz 1f orl $X86_CR4_LA57, %ecx +1: #endif movq %rcx, %cr4 @@ -333,12 +336,7 @@ GLOBAL(name) __INITDATA NEXT_PAGE(early_top_pgt) - .fill 511,8,0 -#ifdef CONFIG_X86_5LEVEL - .quad level4_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE -#else - .quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE -#endif + .fill 512,8,0 NEXT_PAGE(early_dynamic_pgts) .fill 512*EARLY_DYNAMIC_PAGE_TABLES,8,0 @@ -417,6 +415,12 @@ ENTRY(phys_base) .quad 0x0000000000000000 EXPORT_SYMBOL(phys_base) +#ifdef CONFIG_X86_5LEVEL +ENTRY(p4d_folded) + .word 1 +EXPORT_SYMBOL(p4d_folded) +#endif + #include "../../x86/xen/xen-head.S" __PAGE_ALIGNED_BSS diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index e6420b18f6e0..55433f2d1957 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -43,7 +43,7 @@ * before. You also need to add a BUILD_BUG_ON() in kernel_randomize_memory() to * ensure that this order is correct and won't be changed. */ -static const unsigned long vaddr_start = __PAGE_OFFSET_BASE; +static const unsigned long vaddr_start = __PAGE_OFFSET_BASE48; #if defined(CONFIG_X86_ESPFIX64) static const unsigned long vaddr_end = ESPFIX_BASE_ADDR; -- 2.11.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org